Researchers study hair-like protein inside of bacteria

Researchers from Yale have studied a protein inside bacteria that is described as hair-like and acting as an on-off switch for something dubbed nature's "electric grid." Researchers say the ground beneath the surface of the Earth around the entire world is electrically wired by bacteria covered in these hair-like proteins.

Those bacteria and their proteins permeate all oxygen-less soil and deep ocean beds. Before this study, the bacterial hairs were unknown. They're described as the switch that controls the natural electrical grid of the planet. Most living creatures of all shapes and sizes on the planet need to breathe oxygen.

However, some bacteria live in places with no access to oxygen, leading them to evolve a way to live by what researchers describe as "breathing minerals." They're able to breathe these minerals using their extremely small protein filaments called nanowires. Previously, scientists believed these nanowires were made up of a protein called pili, which means hair in Latin.

However, subsequent research published in 2019 and 2020 showed that these nanowires are composed of entirely different proteins. The discovery cast doubt on significant amounts of previous work investigating pili. Yale researchers used cryo-electron microscopy to investigate the pili structure in depth and discovered it's made of two proteins.

Rather than serving as the nanowires directly, pili are hidden inside the bacteria, acting like pistons to push the nanowires into the environment. The study marks the first time this structure has been revealed. Researchers believe that understanding the nanowire structure will allow the tailoring of bacteria to perform a myriad of functions ranging from fighting disease and infections to building living electric circuits. The breakthrough might also lead to the ability to harness bacteria for electricity generation.